Instructions

To prepare the crust:

In a food processor, combine the flour, pecan, sugar and butter. Pulse until the butter becomes pea size. Add egg yolk and mustard, process until incorporated. Put the mixture on a lightly floured board and gather the dough into a smooth ball. Flatten the dough into a disk, wrap it in plastic wrap and refrigerate for an hour.

Preheat oven to 350F. Roll the chilled dough out on a lightly floured surface in between two sheets of plastic wrap to fit your preferred pie pan. (I used a 4 1/4 by 15-inch pan here) If the dough tears, just gently patch it with your fingertips.

Line the dough with a piece of parchment paper, fill with pie weights or dry beans and blind bake for 15-20 minutes until completely done. Remove the weights and parchment paper.

Prepare the filling:

Preheat the oven to 350F.
Heat the oil in a large sauté pan over medium high heat and cook the shallots until caramelized (about 3-4 minutes), add the spinach and cook until wilted. Remove from the pan and set aside to cool. In the same pan, quickly sauté the prosciutto until slightly crisped. They will crisp up more during baking. Remove from the pan.

In a measuring cup, measure the milk, whisk in the eggs, salt, pepper, nutmeg and red pepper flakes until well combined. Layer the shallot and spinach at the bottom of the crust and slowly pour the egg mixture over it.
Top with slices of prosciutto and brie cheese.

Bake for about 30-35 minutes or until the tart is golden brown and the custard is cooked. Sprinkle with freshly chopped thyme and enjoy.